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Old 08-07-2012, 09:26 AM   #26
mopar346
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Re: 454 mileage

I take it they are show tractors.

I thought about a swap last night, and if you did something like a 8.1 conversionfor are going to spend probably 3k to get it right and you will pick up 2-3 mpg, so let's use the high side. If you are currently getting 12 (for easy math) and you go to 15 then you will pick up a gallon every 60 miles, at $3.50 per gallon you would have to run over 51,000 miles to break even.

$3000 / $3.50 = 857.14 X 60 = 51,428

So do it to save money is a misconception, doing it for fun or better power it can be justified because of desire, but not economics. And yes, other swaps can be done more effeceintly but the math is still there and 3 mpg is a pretty good pick up.

Now an LS swap MIGHT make the math work because you will get more than 3 mpg and probably be well less than 2 grand if you plan it right.
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Old 08-07-2012, 10:38 AM   #27
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Re: 454 mileage

I say go with the 454. Your 355 or 350 is not getting super great mpgs anyway. It is unlikely that overdrive will come into play pulling wagons around the farm. The deep torque at low rpms will.

My 355/350 with 3.08 gears X2 peg leg still only got about 10mpgs on the highway. So, 2x the torque and about the same mpgs? Seems good to me. In fact, I had a plan in place, but I did not get to the big block fast enough.
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Old 08-07-2012, 12:25 PM   #28
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Re: 454 mileage

Quote:
Originally Posted by BigBlocksRule View Post
If you can set it up in front of a 4L80E, it will help a lot!

And for all you diesel swap supporters...I can completely overhaul a 454 for less money than you can have a diesel injection system rebuilt. And if I add a turbo similar to what comes stock on most diesel engines, I'll out pull 'em and shave 400lbs off the nose of my truck.
Not really my vortec 454 with a 4L80 In my crewcab gets 10 12 if my wife drives
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Old 08-07-2012, 01:18 PM   #29
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Re: 454 mileage

My '82 K20 (454/SM465/NP205) with 4.10 gears and 35" tires gets 11mpg...loaded or unloaded, trailer or no trailer.
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Old 08-07-2012, 01:36 PM   #30
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Re: 454 mileage

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Originally Posted by redsled87 View Post
I wouldn't swap to a diesel either. For what he is doing, its not worth it. Alot of money for nothing. Maybe he could find an '01 and up 8.1 instead.
That's the issue. It's not a lot Of money if you find a cheap decent running engine. Getting it in there is the issue. Really if he can pull it off it's perfect and will cost as much as a good Lsx swapp with overdrive in the end
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